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Prepublished online as a Blood First Edition Paper on May 1, 2003; DOI 10.1182/blood-2003-03-0744.
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Blood, 1 September 2003, Vol. 102, No. 5, pp. 1869-1871
NEOPLASIA Brief report
Comparison of molecular markers in a cohort of patients with chronic myeloproliferative disorders
Robert Kralovics,
Andreas S. Buser,
Soon-Siong Teo,
Jörn Coers,
Andre Tichelli,
Anthonie P. C. van der Maas, and
Radek C. Skoda
From the Department of Research, Division of Hematology and Department of
Laboratory Medicine, Basel University Hospital, Switzerland; and the
Department of Internal Medicine, Medical Centre Haaglanden, The Hague, The
Netherlands.
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Abstract
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Decreased expression of c-MPL protein in platelets, increased expression of
polycythemia rubra vera 1 (PRV-1) and nuclear factor I-B (NFIB) mRNA in
granulocytes, and loss of heterozygosity on chromosome 9p (9pLOH) were
described as molecular markers for myeloproliferative disorders (MPDs). To
assess whether these markers are clustered in subgroups of MPDs or represent
independent phenotypic variations, we simultaneously determined their status
in a cohort of MPD patients. Growth of erythropoietin-independent colonies
(EECs) was measured for comparison. We observed concordance between EECs and
PRV-1 in MPD patients across all diagnostic subclasses, but our results
indicate that EECs remain the most reliable auxiliary test for polycythemia
vera (PV). In contrast, c-MPL, NFIB, and 9pLOH constitute independent
variations. Interestingly, decreased c-MPL and elevated PRV-1 also were
observed in patients with hereditary thrombocythemia (HT) who carry a mutation
in the thrombopoietin (TPO) gene. Thus, altered c-MPL and PRV-1 expression
also can arise through a molecular mechanism different from sporadic MPD.
 |
Introduction
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Previous reports suggested that decreased expression of c-MPL protein in
platelets and elevated expression of polycythemia rubra vera 1 (PRV-1) mRNA in
granulocytes are characteristic features of patients with polycythemia vera
(PV).1,2
These findings raised hopes that assessing expression of c-MPL and PRV-1 may
replace the need for determining the growth of erythropoietin-independent
colonies (EECs), a valuable but technically demanding assay for
PV.3-5
Since low c-MPL and high PRV-1 also were detected in some patients with
essential thrombocythemia (ET) and chronic idiopathic myelofibrosis
(IMF),1,2,6-8
these markers might define subsets within these myeloproliferative disorder
(MPD) entities. Recently, 9pLOH was described as the most frequent chromosomal
aberration in PV patients, and increased expression of mRNA for the
transcription factor nuclear factor I-B (NFIB) was found in some patients with
9pLOH.9 To determine
whether these markers constitute independent phenotypic variations or appear
clustered in subgroups of MPD patients, we simultaneously determined the
c-MPL, PRV-1, EEC, NFIB, and 9pLOH status in a cohort of 44 MPD patients and
18 healthy control individuals.
 |
Study design
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The study was approved by the Ethics Committee of Basel. Blood was obtained
with written consent. The diagnosis of MPD subtypes was assigned using the
World Health Organization (WHO)
criteria.10
Protein, RNA, and DNA analyses
All blood samples were processed within 1-4 hours of drawing. Isolation of
granulocyte RNA and DNA is described
elsewhere.9 RNA
integrity was assessed using the Agilent 2100 Bioanalyzer (Agilent
Technologies, Palo Alto, CA). Platelets were purified using the sepharose
gel-filtration
method.11 c-MPL
protein expression was determined by immunoblot analysis using the polyclonal
rabbit antibody (CTP7) specific for the C-terminus of human c-MPL (kindly
provided by Dr A. Moliterno and Dr J. Spivak, Johns Hopkins University,
Baltimore, MD). To normalize for platelet protein loading, the membranes were
reprobed using a monoclonal antibody against human CD61 (BD Biosciences, San
Jose, CA). Thrombopoietin (TPO) serum levels were determined using the
TPO-Quantikine ELISA (enzyme-linked immunosorbent assay) (R&D Systems,
Minneapolis, MN).
Real-time polymerase chain reaction
Total RNA (2 µg) was reverse transcribed after random hexamer priming.
To prevent influence from genomic DNA amplification, the primers for RPL19,
PRV-1, and NFIB were designed across exon-intron junctions. The primers for
RPL19 were GATGCCGGAAAAACACCTTG, TGGCTGTACCCTTCCGCTT, CCTATGCCCATGTGCCTGCCCTT
(probe); for PRV-1: CCCCAGCAGACCCAGGA, TTGTCCCCTCCAGACAGCC,
CCATAGACAAGCAGACTGGGCACCTCAA (probe); and for NFIB: CAGTCCACAAACCAGCCAGTC,
GCCGGTAAGATGGGTGTCCTA, GAAAGGAACCAAGCTAGCCCAGGTACCA (probe). The probes were
dual-labeled with 5'-6-carboxyfluorescein (FAM) and
3'-carboxytetramethylrhodamine (TAMRA). The primers for MPL used for
SYBR-PCR were AGCCCTGAGCCCGCC and TCCACTTCTTCACAGGTATCTGAGA. The
CT values were derived by subtracting the threshold cycle
(CT) values for PRV-1, NFIB, and c-MPL from the CT value
for ribosomal protein L19 (RPL19), which served as an internal
control.12 All
reactions were run in duplicate using the ABI 7000 Sequence Detection System
(Applied Biosystems, Foster City, CA).
EEC assay
The clonogenic cultures for erythropoietin-independent colony formation
(EEC assay) were performed using commercial reagents (Stem Cell Laboratories,
Vancouver, BC, Canada).
Detection of 9pLOH
Three highly polymorphic microsatellite markers D9S1779, D9S157,
and D9S161 were used to detect LOH in granulocyte DNA samples as
described.9
 |
Results and discussion
|
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To determine whether alterations in platelet c-MPL protein expression,
granulocyte PRV-1, and NFIB mRNA levels, growth of EECs, and the presence of
9pLOH represent independent phenotypic variations, we examined 44 patients
with MPD (23 PV, 15 ET, and 6 IMF) (Figure
1A). As controls, 18 healthy individuals were included
(Figure 1B). Decreased
expression of c-MPL protein was found in 30% of patients with PV (7 of 23),
40% of ET (6 of 15) and 67% of IMF (4 of 6). Thus, c-MPL cannot be used as a
diagnostic test for PV. To assess whether lower expression of c-MPL is
specific for MPD, we examined a family with hereditary thrombocythemia (HT).
In this family, thrombocytosis is caused by elevated TPO serum levels due to a
splice donor mutation in the TPO
gene.13 We found
lower expression of c-MPL protein in 7 of 8 affected individuals (88%),
despite normal c-MPL mRNA levels (Figure
1C). Hence, decrease of c-MPL protein also can occur in patients
who display sustained thrombocytosis caused by a molecular mechanism different
from sporadic MPD.
PRV-1 mRNA was elevated in 91% of patients with PV (21 of 23), 67% of ET
(10 of 15), and 67% of IMF (4 of 6), whereas growth of EEC was present in 100%
of patients with PV (20 of 20), 69% of patients with ET (9 of 13), and 60% of
patients with IMF (3 of 5). Our results show a higher detection rate of PV
than a recently published study, which reported that only 69% of PV patients
(7 of 13) had elevated
PRV-1.14 This
discrepancy might be due to the smaller number of patients examined in the
previous report. Using the Agilent 2100 Bioanalyzer, we excluded degradation
of the RNA as a potential explanation for low PRV-1 in EEC-positive
individuals. Another difference between the 2 studies is that our PRV-1 assay
is based on primers that span exon-intron boundaries and should therefore be
less influenced by DNA contamination in the patient RNA samples. Irrespective
of the MPD subtype, we observed a strong correlation between PRV-1 and EEC:
84% of patients with EECs had elevated PRV-1 (27 of 32) and, conversely, 94%
of patients with elevated PRV-1 were EEC positive (29 of 31). Interestingly,
we also detected increased expression of PRV-1 in 3 of 4 affected HT family
members who were available for analysis
(Figure 1C). PRV-1 expression
in these individuals did not reach the very high levels observed in most
patients with sporadic MPD. Cytokines can influence PRV-1 expression, for
example, treatment of normal granulocytes with granulocyte colony-stimulating
factor increased PRV-1
mRNA.2 It remains to
be examined whether elevated TPO levels in HT patients might indirectly
influence PRV-1. Importantly, EECs were negative in all affected family
members (Figure 1C). Thus, EECs
remain the most reliable auxiliary diagnostic assay for PV.
Loss of heterozygosity on the short arm of chromosome 9 (9pLOH) was
recently reported to be the most frequent genetic lesion in PV, affecting
approximately 30% of PV
patients.9 In
comparison, deletion of 20q and various chromosome 9 aberrations were
previously reported in 15% and 21% of PV patients,
respectively.15,16
In our present study, 7 of 23 PV patients (30%) displayed 9pLOH, confirming
the previously observed 9pLOH frequency. The 9pLOH also was present in 1
patient with ET. Interestingly, all 8 individuals with 9pLOH were EEC positive
and also displayed elevated PRV-1. Expression of NFIB was hypothesized to be a
consequence of
9pLOH.9 Our study
detected increased NFIB expression in 8 MPD patients with EEC (5 PV, 1 ET, and
2 IMF), but none of these individuals had 9pLOH, indicating that increased
expression of the NFIB gene is independent of the presence of 9pLOH. The
correlation between 9pLOH and increased NFIB in the original report was most
likely a coincidence within a small cohort of 3 patients. No increase in NFIB
mRNA was noted in HT family members (Figure
1C).
The concordance between EEC and PRV-1 markers in MPD patients across all
diagnostic subclasses suggests that they might be caused by a common molecular
mechanism. In contrast, decreased expression of c-MPL appears to be an
independent phenotypic variant. Interestingly, low c-MPL and high PRV-1 also
can occur secondary to elevated TPO in patients with HT. Increased NFIB
expression and presence of 9pLOH are independent of each other but were
detected only in patients with EEC and/or high PRV-1. Larger cohort studies
will be necessary to determine whether MPD subgroups defined by these
molecular markers differ in respect to clinical outcome, for example, leukemic
transformation or hemorrhagic and thrombotic complications.
 |
Acknowledgements
|
|---|
We thank Patricia Frank and Michael Kirsch for technical assistance, and
Alois Gratwohl and Aleksandra Wodnar-Filipowicz for helpful comments on the
manuscript.
 |
Footnotes
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|---|
Submitted March 10, 2003;
accepted April 21, 2003.
Prepublished online as Blood First Edition Paper, May 1, 2003; DOI
10.1182/blood-2003-03-0744.
Supported by grants from the Swiss National Science Foundation, the Swiss
Cancer League, and the Lichtenstein Stiftung (R.K.).
The publication costs of this article were defrayed in part by page charge
payment. Therefore, and solely to indicate this fact, this article is hereby
marked "advertisement" in accordance with 18 U.S.C. section
1734.
Reprints: Radek C. Skoda, Department of Research, Experimental
Hematology, Basel University Hospitals, Hebelstrasse 20, 4031 Basel,
Switzerland; e-mail:
radek.skoda{at}unibas.ch.
 |
References
|
|---|
- Moliterno AR, Hankins WD, Spivak JL. Impaired expression of the
thrombopoietin receptor by platelets from patients with polycythemia vera.
N Engl J Med. 1998;338:
572-580.[Abstract/Free Full Text]
- Temerinac S, Klippel S, Strunck E, et al. Cloning of PRV-1, a novel
member of the uPAR receptor superfamily, which is overexpressed in
polycythemia rubra vera. Blood.
2000;95:
2569-2576.[Abstract/Free Full Text]
- Prchal JF, Axelrad AA. Bone-marrow responses in polycythemia vera
(letter). N Engl J Med. 1974;
290: 1382.[Medline]
[Order article via Infotrieve]
- Weinberg RS. In vitro erythropoiesis in polycythemia vera and other
myeloproliferative disorders. Semin Hematol.
1997;34:
64-69.[Medline]
[Order article via Infotrieve]
- Kralovics R, Prchal JT. Haematopoietic progenitors and signal
transduction in polycythaemia vera and primary thrombocythaemia.
Baillieres Clin Haematol.
1998;11:
803-818.[CrossRef][Medline]
[Order article via Infotrieve]
- Horikawa Y, Matsumura I, Hashimoto K, et al. Markedly reduced
expression of platelet c-mpl receptor in essential thrombocythemia.
Blood. 1997;90:
4031-4038.[Abstract/Free Full Text]
- Le Blanc K, Andersson P, Samuelsson J. Marked heterogeneity in
protein levels and functional integrity of the thrombopoietin receptor c-mpl
in polycythaemia vera. Br J Haematol.
2000;108:
80-85.[CrossRef][Medline]
[Order article via Infotrieve]
- Harrison CN, Gale RE, Pezella F, Mire-Sluis A, MacHin SJ, Linch DC.
Platelet c-mpl expression is dysregulated in patients with essential
thrombocythaemia but this is not of diagnostic value. Br J
Haematol. 1999;107:
139-147.[CrossRef][Medline]
[Order article via Infotrieve]
- Kralovics R, Guan Y, Prchal JT. Acquired uniparental disomy of
chromosome 9p is a frequent stem cell defect in polycythemia vera. Exp
Hematol. 2002;30:
229-236.[CrossRef][Medline]
[Order article via Infotrieve]
- Vardiman JW, Harris NL, Brunning RD. The World Health Organization
(WHO) classification of the myeloid neoplasms. Blood.
2002;100:
2292-2302.[Abstract/Free Full Text]
- Kovacsovics TJ, Bachelot C, Toker A, et al. Phosphoinositide
3-kinase inhibition spares actin assembly in activating platelets but reverses
platelet aggregation. J Biol Chem.
1995;270:
11358-11366.[Abstract/Free Full Text]
- Ghilardi N, Li J, Hongo JA, Yi S, Gurney A, de Sauvage FJ. A novel
type I cytokine receptor is expressed on monocytes, signals proliferation, and
activates STAT-3 and STAT-5. J Biol Chem.
2002;277:
16831-16836.[Abstract/Free Full Text]
- Wiestner A, Schlemper RJ, van der Maas AP, Skoda RC. An activating
splice donor mutation in the thrombopoietin gene causes hereditary
thrombocythaemia. Nat. Genet.
1998;18:
49-52.[CrossRef][Medline]
[Order article via Infotrieve]
- Liu E, Jelinek J, Pastore YD, Guan Y, Prchal JF, Prchal JT.
Discrimination of polycythemias and thrombocytoses by novel, simple, accurate
clonality assays and comparison with PRV-1 expression and BFU-E response to
erythropoietin. Blood.
2003;101:
3294-3301.[Abstract/Free Full Text]
- Westwood NB, Gruszka Westwood AM, Pearson CE, et al. The incidences
of trisomy 8, trisomy 9 and D20S108 deletion in polycythaemia vera: an
analysis of blood granulocytes using interphase fluorescence in situ
hybridization. Br J Haematol.
2000;110:
839-846.[CrossRef][Medline]
[Order article via Infotrieve]
- Najfeld V, Montella L, Scalise A, Fruchtman S. Exploring
polycythaemia vera with fluorescence in situ hybridization: additional cryptic
9p is the most frequent abnormality detected. Br J Haematol.
2002;119:
558-566.[CrossRef][Medline]
[Order article via Infotrieve]

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